Ch. 17 - Chromatography And Instrumentation in ORG Flashcards
What is chromatography?
Chromatography is a technique used to separate different substances in a mixture.
What is the principle behind chromatography?
The principle of chromatography is that a mobile phase (solvent) will carry a dissolved mixture through a stationary phase (paper). The separation occurs as some of the components of the mixture are adsorbed by the stationary phase and move more slowly than those that mix well with the mobile phase.
Mandatory experiment - To separate a mixture of indicators using paper chromatography
-Diagram
-Method
-How is the Rf value calculated?
Apply the mixture using a dropper at 2 cm above the bottom of the sheet. Add water to the gas jar to a depth of 1cm. The sample should be above the solvent. The solvent moves up when allowed to stand for a period of time. A separation of the components of the mixture is seen.
Rf = distance travelled by component / distance travelled by solvent front.
What are applications of gas chromatography?
Drug tests and blood CnH2n+1OH tests.
What are applications of HPLC?
High-performance liquid chromatography is used in the analysis of growth promoters in meat and vitamins in food.
What are applications of mass spectrometry?
To analyse gases from a waste dump or organic pollutants in water.
What is UV absorption spectrometry? Give applications.
Ultraviolet absorption spectrometry is a quantitative technique, it can be used to measure the amount of a substance in a sample.
Analysis of drug metabolites and plant pigments.
What are applications of infrared absorption spectrometry?
It is used to identify plastics and drugs.
